Not long after Alvin surfaced Wednesday evening, RV Atlantis began
steaming west. Moving fast at more than 13 knots, and helped along by a 1-knot
current going our way, the ship traveled 180 nautical miles overnight. At dawn,
we arrived at 88°55W. Below us is a section of the Galápagos
Rift that has never been explored before.

We are like prospectors in a frontier. But rather than gold, we
are searching for hydrothermal vents. The place we have chosen
to look resembles other areas on the mid-ocean ridge where venting
has been found. In particular, we hope to find black smoker chimneys,
whose venting fluids can reach temperatures up to 400°C (750°F).
Only low-temperature vents have been found so far on the Galápagos
Rift.

Along our way, the ships multibeam sonar bounced sound waves off the seafloor
to determine its depth. Dan Scheirer was up early, turning the sonar data into
a map. The map revealed a narrow, shallow valley stretching along an axial high
on the seafloor. The valley is 200 to 400 m wide and 30 to 50 m deep. In such
valleys, called grabens, volcanic and hydrothermal activity are often seen.

Alvin dived to scout out this unexplored
region of the seafloorwith
Expedition Leader Pat Hickey, Co-Chief Scientist Steven Hammond and Dan
Fornari aboard. They landed south of the grabens rim and headed
north toward it. A graben is shaped like a trough. Sometimes, lava will
erupt at the bottom of the trough and spill over the edges. Often it
only fills up part of the trough to create lava lakes. The
surface of these lakes solidifies, like ice atop a pond. But often the
lava drains back down into ocean crust, and the thin surface collapses
under its own weight. It leaves behind a jumble of lava rubble amid a
few tall, solidified columns of lava. It looks a little like the ruins
of an old Roman building whose pillars remain standing after its roof
has collapsed.

We did a lot of bobbing and weaving because the pilot had to be careful
not to bump into the lava pillars, Fornari said. On the pillars, the crew
saw 10-armed sea stars, anemones, and sea pens (so-called because they look like
quill pens). An amazing ray, about 1m across, swam right up to us. Pat
was staring right at it, almost nose to nose.

But at the end of the day, after covering about
1.5 miles, Alvins crew
found no vent animals or any signs of venting. Alvin surfaced.
It was time to call in the hounds.

ABE was unleashed. It will fly east and
west along the graben throughout the night. It will sniff for any telltale signs
of warm water that might lead us to a hydrothermal vent. Meanwhile, under
Bob Colliers direction, RV Atlantis will tow
the CTD overnight along another portion of graben. By morning,
when you read this, ABE and
the CTD will surface to tell us all if the trail here in is
hot, warmor
cold.